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1.
Biosensors (Basel) ; 14(6)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38920616

RESUMO

Optical sensors, especially fluorescence sensors, have been widely used because of their advantages in sensing, such as the high sensitivity, good selectivity, no radiation source, and easy operation. Here, we report an example of fluorescence sensing based on two-dimensional (2D) covalent organic polymers and highlight that the material can achieve a fast response and multi-signal output. This 2DPTPAK+TAPB-based sensor can quickly detect aromatic hydrocarbons and Fe3+ by the fluorescence signal or electrical resistance signal.


Assuntos
Polímeros , Polímeros/química , Técnicas Biossensoriais , Hidrocarbonetos Aromáticos/análise , Corantes Fluorescentes , Espectrometria de Fluorescência
2.
J Am Chem Soc ; 146(7): 4632-4641, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38340061

RESUMO

As fuel and an important chemical feedstock, n-propanol is highly desired in electrochemical CO2/CO reduction on Cu catalysts. However, the precise regulation of the Cu localized structure is still challenging and poorly understood, thus hindering the selective n-propanol electrosynthesis. Herein, by decorating Au nanoparticles (NPs) on CuO nanosheets (NSs), we present a counterintuitive transformation of CuO into undercoordinated Cu sites locally around Au NPs during CO reduction. In situ spectroscopic techniques reveal the Au-steered formation of abundant undercoordinated Cu sites during the removal of oxygen on CuO. First-principles accuracy molecular dynamic simulation demonstrates that the localized Cu atoms around Au tend to rearrange into disordered layer rather than a Cu (111) close-packed plane observed on bare CuO NSs. These Au-steered undercoordinated Cu sites facilitate CO binding, enabling selective electroreduction of CO into n-propanol with a high Faradaic efficiency of 48% in a flow cell. This work provides new insight into the regulation of the oxide-derived catalysts reconstruction with a secondary metal component.

3.
Sci Adv ; 9(43): eadi6119, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37889974

RESUMO

Oxide-derived copper (OD-Cu) is the most efficient and likely practical electrocatalyst for CO2 reduction toward multicarbon products. However, the inevitable but poorly understood reconstruction from the pristine state to the working state of OD-Cu under strong reduction conditions largely hinders the rational construction of catalysts toward multicarbon products, especially C3 products like n-propanol. Here, we simulate the reconstruction of CuO and Cu2O into their derived Cu by molecular dynamics, revealing that CuO-derived Cu (CuOD-Cu) intrinsically has a richer population of undercoordinated Cu sites and higher surficial Cu atom density than the counterpart Cu2O-derived Cu (Cu2OD-Cu) because of the vigorous oxygen removal. In situ spectroscopes disclose that the coordination number of CuOD-Cu is considerably lower than that of Cu2OD-Cu, enabling the fast kinetics of CO2 reaction and strengthened binding of *C2 intermediate(s). Benefiting from the rich undercoordinated Cu sites, CuOD-Cu achieves remarkable n-propanol faradaic efficiency up to ~17.9%, whereas the Cu2OD-Cu dominantly generates formate.

4.
ACS Appl Mater Interfaces ; 7(31): 17061-9, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26167624

RESUMO

A novel Ag/Bi3TaO7 plasmonic photocatalyst has been prepared by a simple photoreduction process. The as-prepared Ag/Bi3TaO7 photocatalyst exhibited an enhanced photocatalytic activity for the degradation of tetracycline (TC) compared to that of a bare Bi3TaO7 catalyst. The 1 wt % Ag-loaded Bi3TaO7 sample showed the highest photocatalytic efficiency for TC degradation (85.42%) compared with those of the other samples. The enhanced photocatalytic activity could be ascribed to the synergistic effect of the surface plasmon resonance caused by Ag nanoparticles. Electrochemical impedance spectroscopy demonstrated that the incorporation of silver nanoparticles onto the Bi3TaO7 surface promoted the separation of photogenerated carriers. In addition, an electron spin resonance (ESR) and trapping experiment revealed that the photoinduced active species hydroxyl radical and superoxide radical were the main active species in the photocatalytic process of TC degradation. The photocatalytic reaction mechanism was discussed by active species trapping and ESR analysis.


Assuntos
Bismuto/química , Prata/química , Tantálio/química , Tetraciclina/química , Catálise , Espectroscopia Dielétrica , Espectroscopia de Ressonância de Spin Eletrônica , Cinética , Luz , Nanopartículas Metálicas/química , Oxirredução , Espectroscopia Fotoeletrônica , Fotólise , Ressonância de Plasmônio de Superfície , Tetraciclina/análise
5.
Zhongguo Zhong Yao Za Zhi ; 34(6): 740-3, 2009 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-19624019

RESUMO

OBJECTIVE: To observe the effect of heart protection on diabetic cardiomyopathy in rats by tripterysium glucosides. METHOD: The rat diabetic cardiomyopathy rats model are made by streptozotocin, then divided into tripterysium glucosides group (n=8) and model group (n=8). In addition, the control group is established (n=8). Glucosides group was orally administrated tripterysium glucosides (18 mg x kg(-1)), the control groups was orally administrated same volume NS for 3 months. Blood sugar, heart function and cardiac index were detected after 3 months. Immunohistochemical techniques were used to detect NF-kappaB and ICAM-1 expression. Ultrastructure of cardiac muscle cell were observed by electronmicroscope. RESULT: Compared with model group, cardiac index was decreased after tripterysium glucosides administration, and LVSP, LVEDP, + dp/dtmax, -dp/dtmax, were improved, and the expression of nuclear Factor-kappaB (NF-kappaB) and intercellular adhension molecule-1 (ICAM-1) was inhibited. Ultrastructure of cardiac muscle cell such as mitochondrion and cardiac muscle fibers was atttenuated. CONCLUSION: Tripterysium glucosides could protect rat diabetic cardiomyopathy rats heart. These function may be related to inflammatory reaction inhibition and immunosuppression of tripterysium glucosides.


Assuntos
Cardiomiopatias/etiologia , Diabetes Mellitus Experimental/complicações , Glucosídeos/farmacologia , Animais , Glicemia/metabolismo , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosídeos/administração & dosagem , Glucosídeos/uso terapêutico , Coração/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/metabolismo , Masculino , Miocárdio/ultraestrutura , NF-kappa B/metabolismo , Ratos
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